Mounting structure for energy absorber

ABSTRACT

A mounting structure for an energy absorber with a mounting hole includes a member, to which the energy absorber is mounted. The member has a rod projecting from a mounting surface thereof. A cylindrical member is fitted onto and engages the rod. The cylindrical member includes a cylindrical portion, and a flanged portion overhanging from the cylindrical portion. The cylindrical portion is inserted into the mounting hole of the energy absorber, and the flanged portion is overlapped with a peripheral portion about the mounting hole.

CROSS REFERENCE TO RELATED APPLICATION

This is a continuation application of PCT/JP00/02405 filed on Apr. 13,2000.

FIELD OF THE INVENTION AND RELATED ART STATEMENT

The present invention relates to a mounting structure for an energyabsorber and, more particularly, to the mounting structure for theenergy absorber which can be suitably applied to a trim of anautomobile.

For energy absorption in the event of a lateral collision, an energyabsorber made of rigid urethane is mounted on a door trim of anautomobile. As an example of method for mounting the energy absorbermade of rigid urethane to the door trim, there is a method usingcaulking as shown in FIGS. 6a and 6 b. FIG. 6b is an enlarged view of aportion VIB of FIG. 6a.

A trim (door trim) 1′ is provided with rods 2′ projecting from an innersurface of the trim 1′. The rods 2′ are inserted through mounting holes4 formed in an energy absorber 3′ for the event of the lateralcollision. After flat washers are fitted onto the rods 2′, the tops ofthe rods 2′ are caulked to form enlarged portions 2′a. To prevent thebacklash of the energy absorber 3′, hot-melt adhesives 6 are affixed ona corner between the side periphery of the energy absorber 3′ and thetrim 1′.

Conventional structure as shown in FIGS. 6a, 6 b requires a step ofcaulking the rods 2′ after the flat washers 5 are inserted and further astep of affixing the hot-melt adhesives 6, taking plenty of time andlabor for mounting the energy absorber.

OBJECT AND SUMMARY OF THE INVENTION

It is an object of the present invention to provide the mountingstructure for an energy absorber for securely mounting an energyabsorber to a member such as a trim without causing backlash and withoutusing hot-melt adhesives.

In a first aspect of mounting structure for an energy absorber of thepresent invention, a rod projecting from a mounting surface of a memberon which the energy absorber is mounted is inserted into a mounting holeof the energy absorber. A cylindrical member having a cylindricalportion and a flanged portion overhanging from the cylindrical portionis fitted onto the rod. The cylindrical portion is fitted into themounting hole of the energy absorber and the flanged portion isoverlapped with a peripheral portion about the mounting hole.

In the mounting structure for an energy absorber, the cylindricalportion of the cylindrical member is arranged between the inner surfaceof the mounting hole of the energy absorber and the outer surface of therod, thereby preventing the backlash of the energy absorber in adirection along the mounting surface. The backlash of the energyabsorber in a direction perpendicular to the mounting surface isprevented by the flanged portion of the cylindrical member which isoverlapped with the peripheral portion about the mounting hole of theenergy absorber. Therefore, the present invention allows the energyabsorber to be mounted to the member such as a trim without usinghot-melt adhesives.

In the present invention, the outer surface of the cylindrical portionis preferably in contact with the inner surface of the mounting hole ofthe energy absorber. As a result of this, the backlash of the energyabsorber in the direction along the mounting surface can be furthersecurely prevented.

In an embodiment of the present invention, the rod is provided with anenlarged portion at an end thereof whereby the cylindrical member isfastened to the rod.

In another embodiment of the present invention, the cylindrical portionis provided with slits extending from an end of the cylindrical portion,the cylindrical portion is provided with a pawl formed on an innersurface of a portion near the end of the cylindrical portion, the rod isprovided with a concavity or convexity formed on an outer surface of therod, and the pawl is engaged with the concavity or convexity whereby thecylindrical member is fastened to the rod.

A second aspect of mounting structure for an energy absorber of thepresent invention is for mounting an energy absorber to a member. Theenergy absorber has a mounting hole. The structure has an anchorprojecting from a mounting surface of the member to enter the mountinghole, a pressing member having a flanged portion pressing the peripheryof the mounting hole and a projection inserted into the mounting hole, aserrate portion provided to one of the anchor and the projection, and anengaging portion provided to the other of the anchor and the projectionto engage with the serrate portion.

According to the mounting structure for an energy absorber of the secondaspect, the backlash of the energy absorber in a direction perpendicularto the mounting surface is prevented by flanged portion of the pressingmember which presses the periphery of the mounting hole of the energyabsorber. The pressing member is designed so as to be in contact withthe inner surface of the mounting hole of the energy absorber, therebypreventing the backlash of the energy absorber in a direction along themounting surface.

According to the present invention, the cylindrical member may have aprojection which is engaged with the energy absorber to prevent therotation of the cylindrical member about the rod. The projection may bea pawl which enters the energy absorber.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view showing a mounting structure for an energyabsorber according to one embodiment of the present invention;

FIG. 2 is a perspective view of a cylindrical member employed in theembodiment;

FIG. 3 is a perspective view of another variation of the cylindricalmember;

FIG. 4 is a perspective view of another variation of the cylindricalmember;

FIG. 5 is a perspective view of another variation of the cylindricalmember;

FIG. 6a is a sectional view showing a conventional mounting structurefor an energy absorber to a door trim, and FIG. 6b is an enlarged viewof a portion VIB in FIG. 6a;

FIG. 7 is a sectional view showing a mounting structure for an energyabsorber according to another embodiment of the present invention;

FIG. 8a is a perspective view of a cylindrical member employed in theembodiment of FIG. 7, and FIG. 8b is a sectional perspective view of thecylindrical member of FIG. 8a;

FIG. 9 is a sectional view showing a mounting structure for an energyabsorber according to further another embodiment of the presentinvention;

FIG. 10 is a sectional perspective view of a cylindrical member employedin the embodiment of FIG. 9;

FIG. 11 is a sectional view showing a mounting structure for an energyabsorber according to an embodiment of the present invention;

FIG. 12a is a perspective view of a cylindrical member employed in theembodiment of FIG. 11, and FIG. 12b is a sectional perspective view ofthe cylindrical member;

FIG. 13 is a sectional view showing a mounting structure for an energyabsorber according to an embodiment of the present invention;

FIG. 14 is a perspective view of a cylindrical member employed in theembodiment Of FIG. 13;

FIG. 15 is a sectional view of a pile of the cylindrical members of FIG.11;

FIG. 16 is a sectional view showing a mounting structure for an energyabsorber according to an embodiment of the present invention;

FIG. 17 is a sectional view showing a mounting structure for an energyabsorber according to an embodiment of the present invention;

FIG. 18 is an exploded view showing the structure of FIG. 17;

FIG. 19 is a sectional view showing a mounting structure for an energyabsorber according to an embodiment of the present invention; and

FIG. 20 is a sectional view showing a mounting structure for an energyabsorber according to an embodiment of the present invention.

DESCRIPTION OF PREFERRED EMBODIMENTS

Hereinafter, embodiments will be described with reference to attacheddrawings. FIG. 1 is a sectional view showing a mounting structure for anenergy absorber according to the first embodiment and shows a section ofa portion similar to a portion shown in FIG. 6b. FIG. 2 is a perspectiveview of a cylindrical member employed in this embodiment.

In this embodiment, a trim 1 is provided with rods 2 which are insertedthrough mounting holes 4 formed in an energy absorber 3, respectively,in the same manner as the conventional one. In this embodiment, acylindrical member 7 is put on the rod 2. The cylindrical member 7comprises a cylindrical portion 7 a and a flanged portion 7 bintegrally. The cylindrical portion 7 a is fitted onto the rod 2 and theflanged portion 7 b is overlapped with the peripheral portion about themounting hole 4. The cylindrical member 7 is put on the rod 2 in such amanner that the cylindrical portion 7 a is fitted into the mounting hole4 and the flanged portion 7 b is laid on the energy absorber 3. Afterthat, the top end of the rod 2 is caulked to form an enlarged portion 2a.

As a result of this, the energy absorber 3 is mounted to the trim 1without causing backlash. That is, the movement of the energy absorber 3in a direction along the surface of the trim 1 is prevented by therespective cylindrical portions 7 a arranged between the rods 2 and theinner surfaces of the mounting holes 4. The movement of the energyabsorber 3 in a direction perpendicular to the surface of the trim 1 isprevented by the flanged portions 7 b of the cylindrical members 7.Therefore, unlike the conventional one of FIGS. 6a, 6 b, hot-meltadhesives are not required, thereby facilitating the work of mountingthe energy absorber 3. In case of mounting the energy absorber to a cartrim, the number of the rods or the mounting holes are preferably 2-6,more preferably 2-4 per one energy absorber.

The diameter (outer diameter) of the cylindrical portion 7 a of thecylindrical member 7 is preferably ±1 mm, more preferably ±0.5 mmrelative to the diameter (inner diameter) of the mounting hole 4 of theenergy absorber 3 before the insertion of the cylindrical portion 7 a.The diameter (outer diameter) of the cylindrical portion 7 a ispreferably 5-12 mm, more preferably 5-10 mm. The diameter (innerdiameter) of the cylindrical member 7 is preferably larger than theouter diameter of the rod 2 by 0.1-2.0 mm, more preferably by 0.5-1.0mm.

The length of the cylindrical member 7 in the longitudinal direction ispreferably 25-100%, more preferably 40-80% of the length of the mountinghole 4 in the longitudinal direction. In case of the energy absorbermade of rigid urethane, the length of the mounting hole 4 in thelongitudinal direction is preferably 4 mm or more, while the cylindricalportion 7 a of the cylindrical member 7 in the axial direction thereofis preferably 3 mm or more, more preferably, 10-15 mm.

The diameter (outer diameter) of the flanged portion 7 b is preferablylarger than the diameter (inner diameter) of the mounting hole 4 by 8-15mm. The thickness of the flanged portion 7 b is preferably 0.5 mm ormore, for example 0.5-2 mm. The material of the cylindrical member 7 ismetal or synthetic resin. The synthetic resin may be polypropylene, ABS,or the like.

Though the flanged portion 7 b of the cylindrical member 7 is formed ina disc-like configuration in FIGS. 1 and 2, the flanged portion 7 b maybe formed in a polygon such as square or hexagon, an ellipse, or astar-like configuration.

In the present invention, the cylindrical member may be provided withprojections 8 c, 9 c, or 10 c as cylindrical members 8, 9, 10 shown inFIGS. 3 through 5. The projections 8 c, 9 c cut into the inner surfaceof the mounting hole 4 while the projections 10 c cut into theperipheral portion around the mounting hole 4, thereby preventing therotation of the cylindrical member 8, 9, 10 about the rod 2. Since thecylindrical member 8, 9, or 10 is fixed to the energy absorber 3, thecylindrical member 8, 9, 10 never rub against to the inner surface ofthe mounting hole 4 of the energy absorber 3, thereby preventing thewear of the inner surface of the mounting hole 4.

The projections 8 c of FIG. 3 are each formed in a triangle and aredisposed at the end of the cylindrical portion 8 a in such a manner thatthe triangle has a steep-back angle toward the other end of thecylindrical portion 8 a in order to allow the easy insertion of thecylindrical portion 8 a into the mounting hole 4. The projection 8 c maybe longer than that shown in FIG. 3 and, for example, may be a trapezoidextending to connect to the flanged portion 8 b.

The projections 9 c of FIG. 4 are each formed in a triangle at thecorner between the cylindrical portion 9 a and the flanged portion 9 b.The projections 10 c of FIG. 5 are formed to project from the peripheraledge of the flanged portion 10 b in a direction along the axialdirection of the cylindrical portion 10 a. Since each of the projections10 c has a sharp tip, the projections 10 c can be easily cut into theperipheral portion about the mounting hole 4 of the energy absorber 3.

According to the present invention, the enlarged portion 2 a can beformed by deformation process such as a US caulking and a tapping-viscaulking. The method for forming the enlarged portion is not limited inparticular.

FIG. 7 is a sectional view of a mounting structure for an energyabsorber according to another embodiment of the present invention, FIG.8a is a perspective view of a cylindrical member employed in thisembodiment, and FIG. 8b is a sectional perspective view of thiscylindrical member.

In this embodiment, the cylindrical member 20 comprises a cylindricalportion 21 and a flanged portion 22 integrally. The cylindrical portion21 is provided with a pawl 23 extending inwardly from the end of thecylindrical portion 21. Arod 26 projecting from a trim 1 is providedwith a concavity 27 formed in the outer surface thereof so that the pawl23 engages with the concavity 27.

The cylindrical portion 21 is formed with slits 24 extending from theend thereof in parallel with the axial direction of the cylindricalportion 21 so that the cylindrical portion 21 can elastically deform inthe radial direction thereof.

To mount the energy absorber 3 to the trim 1, the energy absorber 3 isarranged along the surface of the trim 1 in such a manner that the rods26 are inserted into the mounting holes 4 of the energy absorber 3 andthe cylindrical members 20 are then fitted and pressed onto the rods 26to engage the pawls 23 with the concavities 27. As a result of this, theflanged portions 22 press the peripheral portions about the mountingholes 4 of the energy absorber 3.

The cylindrical portion 21 is formed in a tapered configuration, therebyfacilitating the insertion of the cylindrical portion 21 into themounting hole 4. In a state that the cylindrical member 20 is fitted tothe rod 26 (FIG. 7), the outer surface of the cylindrical portion 21 isin close contact with the inner surface of the mounting hole 4.

The number of the slits 24 is preferably 4-6.

FIG. 9 is a sectional view of a mounting structure of an energy absorberaccording to further another embodiment of the present invention andFIG. 10 is a sectional perspective view of a cylindrical member employedin this embodiment.

In this embodiment, the cylindrical member 30 comprises a cylindricalportion 31 and a flanged portion 32 integrally. The cylindrical portion31 is provided with a concavity 35 clircumferentially formed in theinner surface near the end of the cylindrical portion and with a pawl 33inwardly extending from the end thereof. A rod 36 projecting from a trim1 is provided with a convexity 37 circumferentially formed on the outersurface thereof so that the pawl 33 engages with the convexity 37.

The cylindrical portion 31 is formed with about four to six slits 34extending from the end thereof in parallel with the axial direction ofthe cylindrical portion 31 so that the cylindrical portion 31 canelastically deform in the radial direction thereof.

To mount the energy absorber 3 to the trim 1, the energy absorber 3 isarranged along the surface of the trim 1 in such a manner that the rods36 are inserted into the mounting holes 4 of the energy absorber 3 andthe cylindrical members 30 are then fitted and pressed onto the rods 36to engage the pawls 33 with the convexities 37. As a result of this, theflanged portions 32 press the peripheral portions about the mountingholes 4 of the energy absorber 3.

Though the cylindrical portion 31 is formed in a right circular cylindershape in FIGS. 9 and 10, the cylindrical portion 31 may be formed in atapered configuration similar to the cylindrical portion 21. At least aportion of the outer surface of the cylindrical portion 31 is in contactwith the inner surface of the mounting hole 4.

In any of the embodiments of FIGS. 7 through 10 structured as describedabove, the energy absorber 3 can be mounted to the trim 1 withoutcausing backlash. That is, the movement of the energy absorber 3 in adirection along the surface of the trim 1 is prevented by the respectivecylindrical portions 21, 31 arranged between the rods 26, 36 and theinner surfaces of the mounting holes 4. The movement of the energyabsorber 3 in a direction perpendicular to the surface of the trim 1 isprevented by the flanged portions 22, 32 of the cylindrical members 20,30.

In the present invention, the cylindrical member may be completelyperforated in the longitudinal direction thereof as shown in FIGS. 11through 15.

A cylindrical member 20A shown in FIGS. 11, 12(a) and 12(b) has the samestructure as the cylindrical member 20 shown in FIGS. 7, 8 except thatthe cylindrical member 20A is completely perforated in the longitudinaldirection thereof.

A cylindrical member 30A shown in FIGS. 13, 14 has the same structure asthe cylindrical member 30 shown in FIGS. 9, 10 except that thecylindrical member 30A is completely perforated in the longitudinaldirection thereof.

Since a cylindrical potion 21 of the cylindrical member 20A of FIGS. 11,12(a), 12(b) has a tapered configuration, two or more cylindricalmembers 20A can be compactly piled up by putting the nose thereof intothe end of the cylindrical potion 21 of another one, so that the volumeof the package thereof can be reduced. The pile of the cylindricalmembers 20A is useful in the operation for mounting the energy absorberonto the trim by using it in a manner that the pile is coaxially piercedwith a pole (not shown) so that the cylindrical member 20A is deliveredone by one by being guided with the pole.

The slits 24, 34 formed in the cylindrical potion as shown in FIGS. 7through 14 may partially extend in the cylindrical potion. When thecylindrical members 20, 30 are made up with an elastically deformablematerial such as the synthetic resin, the slits may be omitted.

FIGS. 16 through 20 show embodiments in which the energy absorber 3 ismounted to the trim 1 by fastening a pressing member to an anchor of thetrim with a serrate portion.

In FIG. 16, an anchor 40 is provided to the trim 1 as an insertprojecting from the trim 1. A serrate portion 41 is formed around theanchor 40.

A pressing member 44 has a flanged portion 45, a cylindrical projection46 having a tapered configuration which is inserted into the mountinghole 4, and an engaging portion 47 which is inwardly projected from thefront end of the projection 46.

The pressing member 44 is inserted into the mounting hole 4 so that theflanged portion 45 presses the periphery of the mounting hole 4. Theanchor 40 enters the cylindrical projection 46 so that the engagingportion 47 engages with the serrate portion 41 whereby the pressingmember 44 is prevented from slipping off, thereby preventing the energyabsorber 3 from moving up and down in the figures. The projection 46 isin contact with the inner surface of the mounting hole 4, therebypreventing the energy absorber 3 from moving sidewards in the figures.

In FIGS. 17, 18, an anchor 50 projected from the trim 1 as an insert isprovided with a engaging portion 51 projected from the outer surfacethereof. Apressing member 54 is composed of a flanged portion 55, acylindrical projection 56 which is inserted into the mounting hole 4,and a serrate portion 57 provided to the inner surface of the projection56. The pressing member 54 is pressed into the mounting hole 4 as theanchor 50 enters the cylindrical projection 56 to engage the serrateportion 57 with the engaging portion 51, so that the energy absorber 3is fastened to the trim 1. The flanged portion 55 presses the energyabsorber 3 from above. The projection 56 is in contact with the innersurface of the mounting hole 4, thereby preventing the energy absorber 3from moving sidewards.

In FIG. 19, a pressing member 60 is composed of a flanged portion 63, aprojection 62 inserted into the mounting hole 4, an insert 64 projectingfrom the projection 62 toward the trim 1, and a serrate portion 65provided to the outer surface of the insert 64. An anchor 70 projectingfrom the trim 1 has an engaging portion 71 inwardly projecting from thenose thereof The pressing member 60 is inserted into the mounting hole 4as the insert 64 enters the anchor 70 to engage the serrate portion 65with the engaging portion 71, thereby mounting the energy absorber 3 tothe trim 1.

A pressing member 60A has an engaging portion 65A on the outer surfaceof the nose of an insert 64A. An anchor 70A has a serrate portion 71A onthe inner surface thereof. The structure of the pressing member 60Aother than those described above is the same as that shown in FIG. 19.The same numerals appearing in FIGS. 19 and 20 respectively denote thesame portions.

In FIGS. 19 and 20, the flanged portion 63 presses the energy absorber 3from above, and the projection 62 is in contact with the inner surfaceof the mounting hole 4 to keep the energy absorber 3 from movingsidewards. The projection 62 may have a solid structure.

Therefore, a caulking apparatus is not required according to theembodiments of FIGS. 7 through 20, thereby facilitating the work ofmounting the energy absorber 3.

It should be noted that the cylindrical members of the embodiments ofFIGS. 7-9 may be provided with projections for cutting into peripheralportions about the mounting holes 4 of the energy absorber just like thecylindrical members as shown in FIGS. 3-5.

In the embodiment of FIGS. 11-20, projections for cutting into the innersurface of the mounting holes 4 of the energy absorber may be providedto the cylindrical member or the pressing member.

The form of the serrate portion and engaging portion described above arenot limitative to aforementioned embodiments so long as these portionscan tightly engage with each other. The form of the cylindrical potion,rod and anchor are not especially limitative so long as these portionscan press the energy absorber and keep the energy absorber from movingsidewards.

Though the above-described embodiments relate to the case that theenergy absorber 3 for the event of a lateral collision is mounted to thedoor trim of a vehicle, the present invention can be applied to a casethat an energy absorber made of rigid urethane for protecting the heador the like of a vehicle occupant is mounted to a vehicle member otherthan the door trim. The energy absorber may be made of any materialhaving impact absorbing property such as synthetic resin other thanrigid urethane.

As described above, the present invention allows the easy mounting ofthe energy absorber to a member such as a trim. According to thestructure of the present invention, the energy absorber can be mountedto the member without causing backlash and without using hot-meltadhesives.

What is claimed is:
 1. Mounting structure, comprising: an energyabsorber having a mounting hole, a member, to which said energy absorberis mounted, said member having a rod projecting from a mounting surfacethereof, said rod having a concavity or convexity formed on an outersurface thereof, and a cylindrical member fitted onto and engaging therod, said cylindrical member including a cylindrical portion havingslits extending from an end thereof and a pawl formed on an innersurface of a portion near the end thereof, and a flanged portionoverhanging from the cylindrical portion, said pawl engaging theconcavity or convexity so that the cylindrical member is fastened to therod, said cylindrical portion being inserted into the mounting hole ofthe energy absorber and said flanged portion being overlapped with aperipheral portion about the mounting hole.
 2. Mounting structure asclaimed in claim 1, wherein said rod is provided with an enlargedportion at an end thereof so that the cylindrical member is fastened tothe rod.
 3. Mounting structure, comprising: an energy absorber having amounting hole, a member, to which said energy absorber is mounted, saidmember having a rod projecting from a mounting surface thereof, and acylindrical member fitted onto and engaging the rod, said cylindricalmember having a cylindrical portion, and a flanged portion overhangingfrom the cylindrical portion, said cylindrical portion being insertedinto the mounting hole of the energy absorber so that an outer surfaceof the cylindrical portion contacts an inner surface of the mountinghole, and said flanged portion being overlapped with a peripheralportion about the mounting hole.
 4. Mounting structure, comprising: anenergy absorber having a mounting hole, a member, to which said energyabsorber is mounted, said member having a rod projecting from a mountingsurface thereof, and a cylindrical member fitted onto and engaging therod, said cylindrical member having a cylindrical portion, a flangedportion overhanging from the cylindrical portion, and a projectionengaging with and cutting into the energy absorber to prevent thecylindrical member from rotating about the rod, said cylindrical portionbeing inserted into the mounting hole of the energy absorber and saidflanged portion being overlapped with a peripheral portion about themounting hole.
 5. Mounting structure, comprising: an energy absorberhaving a mounting hole, a trim of a vehicle, to which said energyabsorber is mounted, said trim having a rod projecting from a mountingsurface thereof, and a cylindrical member fitted onto and engaging therod, said cylindrical member having a cylindrical portion, and a flangedportion overhanging from the cylindrical portion, said cylindricalportion being inserted into the mounting hole of the energy absorber andsaid flanged portion being overlapped with a peripheral portion aboutthe mounting hole.
 6. Mounting structure, comprising: an energy absorbermade of synthetic resin including rigid urethane and having a mountinghole, a member, to which said energy absorber is mounted, said memberhaving a rod projecting from a mounting surface thereof, and acylindrical member fitted onto and engaging the rod, said cylindricalmember having a cylindrical portion, and a flanged portion overhangingfrom the cylindrical portion, said cylindrical portion being insertedinto the mounting hole of the energy absorber and said flanged portionbeing overlapped with a peripheral portion about the mounting hole. 7.Mounting structure for mounting an energy absorber with a mounting holeto a member, comprising: an anchor projecting from a mounting surface ofthe member to enter the mounting hole, a pressing member having aflanged portion for pressing a periphery of the mounting hole and aprojection entering the mounting hole, said pressing member contactingan inner surface of the mounting hole of the energy absorber, a serrateportion provided to one of the anchor and the projection, and anengaging portion provided to the other of the anchor and the projectionto engage the serrate portion.
 8. Mounting structure for mounting anenergy absorber as claimed in claim 7, wherein one of the anchor and theprojection is a cylindrical member and the other is an insert memberinserted into the cylindrical member, at least one of an inner surfaceof the cylindrical member and an outer surface of the insert memberhaving said serrate portion.
 9. Mounting structure for mounting anenergy absorber as claimed in claim 7, wherein said pressing memberincludes a projection engaging the energy absorber to prevent thepressing member from turning around the anchor.